By CBS3 Staff

PHILADELPHIA (CBS) — The Eagles play their first preseason game Thursday against the Steelers at Lincoln Financial Field. In the wake of Philadelphia’s new indoor mask mandate, the team’s front office says fans will be required to wear a mask when they are indoors at the stadium.

Fans in the outside seats will not be required to mask up.

READ MORE: FDA Authorizes Pfizer's COVID-19 Booster Shot For Americans Over 65, Those At High-Risk

The organization also says fans should bring their own masks. Those who are unvaccinated are strongly encouraged to wear a mask at all times.

Meanwhile, the Phillies are also requiring masks in all indoor areas, beginning Thursday for a 1:05 p.m. start vs. the Los Angeles Dodgers.

Masks must be worn in the Diamond Club, restrooms, elevators and team stores.

MORE NEWS: 3 Men Injured In Wynnefield Shooting, Police Say

Philadelphia officials announced a new mask mandate Wednesday that will take effect at midnight Thursday. Face coverings must be worn inside unless the business requires proof of vaccination.